Wheel cushioning structure



Jan. 5, 1960 A. L. EVERITT 2,919,737

WHEEL 'CUSHIONING STRUCTURE Filed Dec. 23, 1957 2 Sheets-Sheet 1INVENTOR.

Allen L. Ever/H F/'g../ BY

' 1's Attorney Jan. 5, 1960 A. L. EYERITT WHEEL CUSHIONING STRUCTURE 2Sheets-Sheet 2 Filed Dec. 25, 1957 INVENTORf Allen 1.. Evn'fl I D D lDcHis Attorney United States Patent WHEEL CUSHIONINGaSTRUCTURE Allen- L.Everitt,= Dayton, Ohio; assignorto General- Motors Corporation, Detroit;Mich acorporation'of Delaware Application December 23, .19 'i, SerialNo. 704,754.

4Claims. (Cl': 152-47) Thisinvention relates to vehicle wheels, and,particularly, to a cushioned wheel utilizing a plurality ofpreassenibled, preloaded. bushings. to, absorb. torsional vibrationsaswell as radial and: axial loads transmittedto, the wheel I Anobject ofthis invention, is;to.provide a new and improvedwheel cushioningStructure utilizing a plurality of, preloaded shear bushingspressed-between equal area surfaces in pairs concentrierelative to.each, other and of substantially equal areas relative to each other fortorsional and axial stressing-of each preloaded elastomeric bushingbetween each pair of surfaces.

Another objectof this inventionis to provide a wheel cushioningstructure including an outer annular rim portion having an axiallyextending. annular flange portion and an innenannular rimportion'havingan annular flange portion extending axially and concentricallynelatiye.to the .outer flange portion with a-. surface substantially equal inarea. to a surface of, the;v inner flange portion, a preloadedtorsional; elastomericbushing. pressed between the inner and. outer;flange portions, and a pair of axial-control elastomeric: beads. orrings of annular shapeeach preloaded. between-.substanially equalarearadial and annular surface'portions carried by theinner andouter rimportions to limit axial or lateral. movement of the inner. and outer rimportions relative to each, other while the preloaded bushingaids both inopposing axial or lateral movement and in pposing torsional deflectionofthe inner and outer rim portions relative to .each other.

' Another, object of this inventionisto provide a; road wheelconstruction wherein a wheel. disc connecting a tire mounting rim .and.a hub is-divided intotwo annular portions having axial complementary.flange portions inelnding an outer disc portion supported relative to aninner disc portion only by means of a preloaded 5 elastomeric axialbushing means engaging the axial complementary disc flange portions andincluding preloaded elastomericbushings for limiting relative axialmovement of the .disc portions all cooperating to provide artorsionalcushion eliminating any: sliding engagement of the inner or outer discportions relative to each other or, relative toanyother wheel part forreducing strain and; resulting wear on component parts of the wheeland'for shock, loading inducedv by. acceleration or deceleration of ,a.vehicle thereby.reducingtorsional vibration noises oftenv caused bybrake: application, final or rear axle drive, and other sources suchastire noise androad surface irregularities.- 7

Another object. ofhthis invention is to provide a wheel cushioningstructure wherein a wheel discconnecting a tire .mou'ntingrim and a hubis; divided into two annular. portions, having axial complementaryflange portions;spaced, from each, otherand supported relative to eachother only by a preloaded elastomeric bushingfor opposing torsional andaxial deflections ofthe rim relatiye .to the,hubv and wherein each-.1ofthe.,.annular wheel dislcportions. carries radial flangeportions. whichare spaced longitudinally. relative to, each other at each of referencebeing had: to the accompanying drawings.

wherein apreferred embodiment ofthe present invention is clearly shown.

In the drawings:

Fig. 1- is a cross sectionalaelevational view of awheel cushioningstructure. in accordance; with the present invention.

Fig. 2 is .an exploded cross. sectional .elevational view of a wheeldisc cushionsubassembly: for use in thewheel structure of Fig. 1. ,7 p

The wheel as shown in Fig. Icomprises an outer rin' 10 having flangeportions; 10;; andv10b against which tire beads 11a and .11b are.pressed: in sealing engagement. The outside rim entire-mounting annularmember 10 is provided with-an-inner portion 12 intermediate the flanges10a and 10bsand isiadapted to be supportedby a lateralflange'orcylindrieal portion 13 of an outer rim or disc member 1311;.The disc;,13d is one part of a subassembly generallyindicatedby; numeral20.whichis provided between the. tiremountingrim and a wheel hub- 21provided with-a. radially outwardly extendingflange 22-. Thesubassembly: 2 0. alsov includes an inner annular disc portion; or,member 23d having a radially inwardly extending flangegportion 23. whichis provided with apertures 23d locatedabout aperipheral surface of theradial flange 23.; The hub flange 22 carries a. plurality of studs 24.havinggthreaded ends Me which project through the apertures 23a andontowhich nuts or bolts 24b are threaded. tofastenvthetwheel in a usual'manner to the hub 21. i I

Secured between. the disc 23zand hub flange 22 there is,a flange portionor radiallyinwardly, extending mem ber 26. of a brake drum 28 having a.braking surface 28s extending longitudinally and axially of the hub 21.The hub 21 is provided with-aflange portion 21 having a shoulder 21salong an inner peripheral surface thereof; adapted to. be engaged byabearing 29 with an outer race in engagement with theflange 21f of thehub and aninner race in engagement. withya cylindrical portionof an axle3. The axle; has a reduced diameter portion 30d with a threaded: end.30eontqwhichanut orbolt 3% is threaded for retaininga bearing 31 betweenthe reduced diameter portion 30 and an, outwardly extending annularflange orshoulder-Z lb of the hub 21. The nut 30b is provided with aplurality of radially outwardly extending slots 30s so thata, cotter pincanbe inserted through an aperture 30a. of-theaxle when one pair ofslots 30s are aligned relative to the aperture 304 for insertion andcrimpingover-of; the: end of such a cotter pin generally usedto.lock--the.-nut 3012 against; rotation relative to the endof theaxle}. A protective cap, hub, or grease cup 32is'pressflttedinside-aradial inner surface of an end Me of the :lrub;21'.

The subassembly 20' of -the. presentinvention further:- includes flangeportions v13 and; Bf-provided. extending; longitudinally and andconcentrically relative toyeach other but spaced a predetermineddistance from; each other radially between flange 131i and} .fla lgfi.f10fth6. annular disc members 13d-and23d, respectively? The flange13f,has a surface 13s along;;a;-.-r adialinner periphe ery thereof which issubstanially equal;to a. surfacearea 23s along the radially outerperiphery of .fiange'xzfifz: The surfaces 13s and 23s areradiallyaligned jand-:.p i.

le Batented Jan. 5, 1960 downs? tioned concentrically and axiallyrelative to the hub portion 21b and reduced diameter axle portion 30d asillustrated in the wheel assembly of Fig. 1.

The outer annular disc or web 13d has a radially inner flange 130 whichis parallel to and spaced from disc 23d. The disc or outer rim 13d alsocarries an intermediate flange portion 13i having a radial outer annularend or flange 13:: provided with apertures through which a rivet 13x isinserted and secured by flattening of opposite end heads of the rivet ina usual manner. It is to be understood that the radial outer end flange13:: can also be welded or otherwise suitably secured to the outer rimor web 13d. The intermediate flange portion 131' is provided with aninner radial surface or wall portion 13w which is complementary to aradially outwardly extending end 23a of innerrim or web 23d having awall 23v facing the wall 13w but spaced therefrom. Similarly, theradially inwardly extending flange 130 of the outer rim or web has aninner surface or wall portion 13a which faces an outwardly extendingsurface or wall portion 23w provided on the inner disc 23. The surface13a extends radially outwardly and is spaced axially and longitudinallyrelative to the surface portion or wall 23w as is obvious from thedrawings.

In accordance with the present invention, a plurality of annularelastomeric bushings are inserted easily and in a short period of timein a preloaded condition between complementary surfaces of the outsiderim, disc or web 13d and the inside rim, disc or web 230'. One of thesebushings or rings is generally indicated by numeral 30 and, as isvisible in Fig. 2, this ring 30 is shaped originally having asubstantially square or rectangular cross section which is pressedbetween flanges 13) and 23f and into engagement with surfaces 13s and23s, respectively, for supporting the outside rim 13d radially outwardlyfrom the inside rim or web 23d. Since the areas of surfaces 13s and 23sin engagement with the elastomeric bushing or ring 30 are substantiallyequal to each other, the inner and outer rims are retained in anassembled relationship relative to each other by a resilient preloadingprovided by the elastomeric bushing 30 such that there is no tendencyfor the inner and outer rim members to separate and explode out ofassembled relationship. The ring 30 can be bonded or cemented to thesurfaces 13s and 23s or can be only pressed into tight resilientengagement therewith so that the preloaded forces tend to retain thebushing 30 and inner and outer rim members in assembled relationship.

The bushing 30 is compressed between the surfaces 13s and 23s from aninitial inner diameter D of the ring 30 to a larger inner diameter D ofthe surface 23s. Also the outer diameter D of the elastomeric ring 30 isreduced to a smaller inner diameter D of the flange portion 13 alongradially inner surface 13s. The structure obtained by compressing theelastomeric ring 30 radially between the surfaces 13s and 23s provides atorsional cushion at the wheel for shock loading induced by accelerationor deceleration of a vehicle and reduces torsional vibration noisesexcited by brake applications, final or rear axle drive transmittingforces to the wheel, and other noise sources such as tire noises androad surface irregularities otherwise transmitted from the rim throughthe axle to the vehicle. Due to the preload rubber mounting provided byuse of elastomeric bushing 30 between substantially equal surface areas13s and 23s, there is both a torsional and a lateral or axial deflectingforce available for maintaining a substantially constantly variabledamping of any shocks including shearing or axial forces to which thewheel may be subjected relative to the hub and axle. Axial play of thewheel rim outer portion relative to the wheel rim inner portion iscontrolled but not eliminated by use of the elastomeric bushingsupporting the outer rim portion on the inner rim portion.

- The subassembly illustrated in the exploded view of Fig. 2 furtherincludes a pair of elastomeric bushings 33 and 43 each originally havinga substantially square or rectangular cross section while in a naturalor uncompressed condition. These bushings 33 and 43 are compressedlaterally and spread radially whereas the clastomeric bushing 30 iscompressed radially and spread laterally and longitudinally of the axisof the hub 21. Bushing or control pad 33 has an uncompressed thickness33T which is reduced to a thickness 33t when the bushing 33 is pressedbetween surfaces of wall portions 13w and 23v. The bushing 43 has aninitial thickness 43T which is reduced to a thickness 4312 when thebushing 43 is pressed between the wall surface portions 13a and 23w. Thepad or elastomeric ring 33 opposes axial shifting of the flange end 23::of the inner rim 23d relative to the intermediate flange portion 131' ofthe outer rim or member 13d. The elastomeric bushing 43 opposes lateralor axial shifting of the inner disc 23d relative to the surface Wallportion 13a of radial flange 13r of the outer rim member 13d and viceversa. The preloaded effect of the bushings 30, 33, and 43 serves tocushion flange portions of the inner and outer disc or web membersrelative to each other such that torsional. and axial movements orforces are counteracted by inherent resilience of the bushings due tothe compression thereof between various surface areas of the flange pottions as described above. It is obvious that the bushings flange portion131' and inner rim 23d, respectively, tending to control and contain thepreloaded bushings 33, 43, and 30 in concentric and preloaded conditionrelative to each other and the surfaces they engage as illustrated inthe view of Fig. 1. Lateral control axially with the wheel isaccomplished by the bushings preloaded at assembly. This provides a highlateral rate axially with the elastomeric material in compression.Because of the preload at assembly, the rings 33, 43 also carrytorsional loads in shear thus helping to reduce torsional stresses onthe bushing 30.

Among the advantages of the construction for the wheel cushioningstructure of the present invention is the reduction of torsionalvibration noises excited by brake application, tire noises and roadsurface irregularities. Using rings 33, 43 and bushing 30 eliminatesmetal to metal contacts between disc portions avoiding a lubricationproblem and reducing undesirable noise encountered with slidingengagement of any disc portion relative to other wheel parts. Theplurality of preloaded bushings can be preassembled easily intosubassembly 20 for use to absorb torsional vibrations and since therubber or elastomeric material is compressed under torsional forces aswell as radial and even axial loads in the plane of the wheel, lateralmovements parallel to the axis of hub or axle are also counteracted bythe resilient preloaded bush ings. A cushioned yet very strong preloadedjoint is provided between the inner and outer rim portions due to theaxial and torsional preloading of plurality of rubber or elastomericmaterial bushings. The parts illustrated in the exploded view of Fig. 2are easy to assemble and retain in assembled relationship due to thetelescoping character of the inner and outer rim portions relative'tothe plurality of bushings 30, 33, and 43 locked together by fasteningthe intermediate flange portion or disc 13i securely against the outerrim member 13d by use of rivets 13x or other suitable fastening meanssuch as welding around the periphery of the disc. Also to be noted isthat when preloaded rubber is used for bushings 30, 33, and 43, theresilience or life of the rubber is prolonged'because rubber ismaintained resilient as acushion'lon'ger' when prestressed or compressedby mounting means such as the subassembly 20 for the wheel cushioningstructure of the present invention. When rubber is left in a natural orun-preloaded condition the resilience and life thereof is rapidly lostdue to aging and hardening of the unstressed rubber material. In thebushings 30, 33, and 43, the preloading provided by the structure of thepresent invention assures continuous cushioning of axial and torsionalforces encountered between the hub and tire rim.

While the embodiments of the present invention as herein disclosedconstitutes a preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. A road wheel construction for use in supporting a vehicle tiremounting rim relative to a hub, comprising, inner and outer discportions having flanges remote from said rim as well as said hub andproviding inner and outer annular surfaces of substantially equal arearelative to each other, said inner and outer surfaces being concentricrelative to each other, flange portions extending radially of the huband carried by said inner and outer discs, said radial flange portionsbeing spaced longitudinally from each other and a plurality of preloadedelastomeric bushings provided between said inner and outer disc portionsand including a pair of rings compressed between said radial flangeportions at each of opposite ends of the inner and outer concentricsurfaces as well as an annular bushing compressed between said inner andouter concentric surfaces of substantially equal areas, said latterbushing providing preloading force for cushioning axial as well astorsional deflections of said inner and outer disc portions relative toeach other.

2. The road wheel construction of claim 1 in which said plurality ofpreloaded elastomeric bushings are each deformed to a stressedsubstantially rectangular shape from a natural substantially squareshape and thereby provide cushioning of both axial and torsional forcesencountered by said inner and outer disc portions used for supportingthe tire mounting rim relative to the hub.

3. In a road Wheel construction for use in supporting a vehicle tiremounting rim relative to a hub, a Wheel disc subassembly for cushioningaxial and torsional shock forces between the rim and hub, comprising,inner and outer annular portions having axially extending flangeportions radially spaced from each other and remote from said rim andhub, a preloaded elastomeric bushing provided between said flangeportions and resiliently supporting said inner and outer annularportions relative to each other and used for opposing torsional andaxial deflections of the rim relative to the hub and vice versa, radialflanges carried by each of said annular portions and spacedlongitudinally relative to each other, and preloaded elastomeric ringmeans provided at each end of said preloaded bushing and compressedbetween said radial flanges for aiding in controlling axial andtorsional deflection as opposed by said preloaded bushing.

4. The subassembly of claim 3 in which said preloaded bushing and ringmeans are compressed from a naturally greater thickness to a smallerthickness between said radially spaced flange portions and radialflanges and thereby are stressed to prolong resilience of the cushioningprovided by said preloaded ring means as well as said preloaded bushing,said preloaded bushing and ring means providing the only supportradially and axially between said inner and outer annular portions.

References Cited in the file of this patent UNITED STATES PATENTS1,444,048 Walther Feb. 6, 1923 2,004,922 Bourdon June 18, 1935 2,609,856Patch Sept. 9, 1952 FOREIGN PATENTS 37,010 Netherlands Dec. 16, 1935

